Well, this is really disappointing. Especially after being told "if you don't want music theory don't ask questions like that! We'll never stop!"

Stim gave me a clear and concise rule to tell whether a song is in a major or minor key. I thought I was on my way to finally understanding something about music theory. But that clear and concise rule hinges on what the first step of the scale is, and now it seems that no one can give a clear and concise rule as to what determines the first step of the scale, other than that it's whatever the person who wrote the score decided was the first step and so indicated in the key signature.

So if I write a song using no sharps or flats, and sign it with a single sharp, but in front of all the f's in the melody I put a natural sign, that means the song is in the key of G? And if I write the same melody again, this time signing it with two sharps and putting natural signs in front of both the f's and the c's, is the song now in D-minor? How about if I also sign it J.S. Bach, does that mean it was written in the 18th century?

And since I don't have the version of Misirlou that I learned as a child written in dots, I'm told that I can "count the sharps or
flats". As I said previously, that melody uses a b c d e f and g#. There's only one sharp. So it's in the key of G? Then how can I tell whether it's major or minor? What's the first step of the scale when g isn't even used in the melody?